1. Field of the Invention
The present invention relates to rotating magnetic disk drives, and more particularly, to a disk drive having a hybrid spindle speed control system for maintaining disk rotation speed during a high-speed seek.
2. Description of the Prior Art and Related Information
In order to remain competitive, disk drive manufacturers must continually provide increased data storage capacity and access rate while rigidly controlling disk drive manufacturing cost. One key to increased access rate is increased disk rotation speed. The disk is rotated at a constant angular velocity by a spindle motor in response to a spindle control current. The spindle motor current may be generated based on a measured time between servo wedges on the disk. However, measuring the time between servo wedges may be problematic during a high-speed seek.
Accordingly, there exists a need for a technique for robustly maintaining a disk rotation rate during a high-speed seek.